High-speed low-voltage electro-optic modulator with a polymer-infiltrated silicon photonic crystal waveguide

Abstract

A novel electro-optic silicon-based modulator with a bandwidth of 78GHz, a drive voltage amplitude of 1V and a length of only 80 microm is proposed. Such record data allow 100Gbit/s transmission and can be achieved by exploiting a combination of several physical effects. First, we rely on the fast and strong nonlinearities of polymers infiltrated into silicon, rather than on the slower free-carrier effect in silicon. Second, we use a Mach-Zehnder interferometer with slotted slow-light waveguides for minimizing the modulator length, but nonetheless providing a long interaction time for modulation field and optical mode. Third, with this short modulator length we avoid bandwidth limitations by RC time constants. The slow-light waveguides are based on a photonic crystal. A polymer-filled narrow slot in the waveguide center forms the interaction region, where both the optical mode and the microwave modulation field are strongly confined to. The waveguides are designed to have a low optical group velocity and negligible dispersion over a 1THz bandwidth. With an adiabatic taper we significantly enhance the coupling to the slow light mode. The feasibility of broadband slow-light transmission and efficient taper coupling has been previously demonstrated by us with calculations and microwave model experiments, where fabrication-induced disorder of the photonic crystal was taken into account.

Design and optimization of photonic crystal fiber for liquid sensing applications

“…Photonic crystal fibers (PCFs) have been attracted a great deal of attention for its incredible performance and large variety of applications. PCF can be used as filters [1], switches [2,3], electro-optical modulators [4,5], polarization converters [6], sensors [7][8][9][10][11][12][13][14][15][16][17], etc. PCF based sensors are smart applications in fiber optic technology which have been investigating and developing since last decade.…”

“…In PCF 3 , optimized values of air holes diameter have been kept as d 2 =d 3 <d 1 =d 4 . However, we have turned into PCF 4 and achieved higher sensitivity by replacing the group of tiny holes with a single hollow core filled with same analyte to be detected. The hollow core area is same as the area covered by supplementary tiny holes.…”

“…These supplementary core holes are arranged with the hole to hole pitch distance denoted by a. Figure 2 visualizes the enlarged view of core of PCF 1 , PCF 2 , PCF 3, and the replacement of hollow channel instead of using a group of tiny channels in PCF 4 . Diameter of the hollow channel is D 2 =1.70 m, which is same as the diameter of the region of supplementary holes in the core (D 1 =D 2 ).…”

“…Diameter of the hollow channel is D 2 =1.70 m, which is same as the diameter of the region of supplementary holes in the core (D 1 =D 2 ). Figure 3 shows the computational region of the proposed PCF 3 and PCF 4 , which is divided into homogeneous triangular pieces forming a mesh. Each of the PCFs has two orthogonal sides of the computational region which are assigned with two artificial boundary conditions: perfect electric conductor (PEC) and perfect magnetic conductor (PMC).…”

Electro-optic modulation in slotted resonant photonic crystal heterostructures

“…[6][7][8] Concepts based on slotted photonic crystal ͑PhC͒ waveguides can exploit slow light mechanisms or high quality factor cavities to achieve very compact device dimensions and have been discussed recently. [9][10][11] We propose a concept using a double heterostructure cavity [11][12][13] in a slotted silicon PhC waveguide, infiltrated with NLO-polymer to operate as an EO-modulator. Figure 1 shows a scanning electron micrograph of the structure.…”